Chronic methanol toxicity through topical and inhalational routes presenting as vision loss and restricted diffusion of the optic nerves on MRI: A case report and literature review.

Methanol intoxication can cause irreversible neurologic sequelae if unrecognized and untreated. Ingestion is the most common form of toxicity; however, dermal and inhalational exposures likewise occur but are documented rarely. While acute intoxication is commonly encountered, chronic exposure to methanol should also be highlighted. We report a case of a 57-year old female presenting in the emergency room with progressive dyspnea, metabolic acidosis with high anion gap, and metabolic encephalopathy. After emergency hemodialysis, the patient complained of vision loss on both eyes. Initial non-contrast cranial magnetic resonance imaging (MRI) revealed restricted diffusion of the intraorbital segment of both optic nerves. A thorough history revealed that she was applying a clear colorless liquid bought online all over her body for alleged pruritus for more than a year. The syndrome of metabolic acidosis with high anion gap, metabolic encephalopathy, vision loss, and laboratory findings led us to suspect a diagnosis of chronic methanol poisoning with an acute component. The liquid in question was sent for chemical analysis and result showed that it consisted of 95.5% Methanol. This case highlights the need for high index of clinical suspicion for methanol toxicity in the absence of oral consumption, the complications of chronic form of methanol intoxication, and the uncommon radiologic finding seen in diffusion-weighted imaging (DWI).

Autosomal Dominant Frontotemporal Lobar Degeneration in a Filipino Family with Progranulin Mutation.

BACKGROUND: Compared to Western populations, familial frontotemporal lobar degeneration (FTLD) is rare among Asians. Progranulin (GRN) gene mutation, which is a major cause of FTLD, is likewise rare. We present a family with FTLD from the Philippines with an autosomal dominant pattern of inheritance and GRN mutation and briefly review reports of GRN mutations in Asia. CASE PRESENTATION: The proband is 66 years old with progressive nonfluent aphasia (PNFA)-corticobasal syndrome . We assessed 3 generations of her pedigree and found 11 affected relatives with heterogenous phenotypes, usually behavioral variant frontotemporal dementia (FTD) and PNFA. Neuroimaging showed atrophy and hypometabolism consistent with FTD syndromes. White matter hyperintensities were seen in affected members even in the absence of vascular risk factors. A GRN mutation R110X was found in 6 members, 3 with symptoms and 3 were asymptomatic. Plasma GRN was low (<112 ng/mL) in all mutation carriers. No mutations were found in microtubule-associated protein tau, APP, PSEN1, and PSEN2 genes, and all were APOE3. CONCLUSION: This is the first Filipino family with autosomal dominant FTD documented with GRN mutation. Identifying families and cohorts would contribute to therapeutic developments in an area with FTD-GRN.

Effects of Ginkgo biloba on cerebral blood flow assessed by quantitative MR perfusion imaging: a pilot study.

INTRODUCTION: Extract of Ginkgo biloba (EGb), a dietary supplement used for a number of conditions including dementia, has been suggested to increase cerebral bloodflow (CBF). The purpose of this study was to determine if changes in CBF could be detected by dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI)in elderly human subjects taking EGb. METHODS: DSC-MRI was performed in nine healthy men(mean age 61±10 years) before and after 4 weeks of 60 mg EGb taken twice daily. One subject underwent six consecutive scans to evaluate intrasubject reproducibility. CBF values were computed before and after EGb, and analyzed at three different levels of spatial resolution, using voxel-based statistical parametric mapping (SPM), and regions of interest in different lobes, and all regions combined. RESULTS: Normalized intrasubject CBF (nCBF) measurements had a standard deviation of 7% and 4% in gray and white matter (WM) regions, respectively. SPM using an uncorrected, voxel-level threshold of P≤0.001 showed a small CBF increase in the left parietal-occipital region.CBF in individual lobar regions did not show any significant change post-EGb, but all regions combined showed a significant increase of non-normalized CBF after EGb (15% in white and 13% in gray matter, respectively, P≤0.0001). CONCLUSION: nCBF measured by DSC-MRI has good intrasubject reproducibility. In this small cohort of normal elderly individuals, a mild increase in CBF is found in the left parietal-occipital WM after EGb, as well as a small but statistically significant increase in global CBF.

Neuroimaging findings in a child with dumbbell-shaped frontosphenoidal dermoid cyst presenting as preseptal cellulitis.

We report the CT and MRI findings in a 5-year-old girl with histologically proven frontosphenoidal dumbbell-shaped dermoid cyst with sinus tracts in the frontal bone extending to the dura. Although the most common location for dermoid cyst in the head and neck is at the frontosphenoidal region, presentation with a tract extending deep to underlying bone or the intracranium is rare for this location. Complete surgical excision has been widely accepted as the basic treatment for dermoid cyst. However, the relatively extensive nature of such surgical interventions may be associated with serious risks to both visual acuity and cosmesis. From a clinical viewpoint, even if these are rare cases, radiological imaging is crucial for orienting the deeper extension of the lesion for presurgical planning.